: We propose to evaluate the periodontal disease, microbiology and immunology of a large adult Type 1 diabetic cohort and previously identified health control population. In 1992-1994, the University of Pittsburgh's Oral Health Science Institute (OHS) completed periodontal assessments of 406 subjects being followed by the ongoing University of Pittsburgh Epidemiology of Diabetes Complications Study (EDC). We propose to continue our collaboration by reexamining subjects in this cohort, who will now be 30 to 55 years old. This exploratory proposal will determine the prevalence, incidence and 10-year progression of periodontal disease of Type 1 diabetic and nondiabetic control subjects, and characterize the periodontal microflora and immune response within these populations. The overall goals of this proposal are to assess the impact of periodontal risk factors (diabetes, smoking, age of onset, elevated glucose, etc.) on disease progression microbiotas and immune responses. Additionally we plan to explore the interrelationships between periodontal infections and the incidence of coronary artery disease complications in this high-risk population. Because we have 10-year baseline periodontal disease data, we will be able to determine not only the prevalence, but also the incidence and site-specific progression of periodontal disease within this adult Type 1 diabetic cohort and an age-matched nondiabetic control group. In collaboration with the microbiology laboratory at Forsyth Dental Institute, we will be able to identify and quantify the gingival and periodontal microflora found within healthy and diseased sites of these populations. The impact of diabetic glycemic control (GhbA1, GhbA1-months, elevated fasting blood glucose) as well as salivary and GCF glucose concentrations will also be evaluated. The integration of this 10-year follow-up periodontal, microbiologic and immunologic assessment by the University of Pittsburgh's Oral Health Science Institute (OHSI) into this ongoing medical epidemiologic study (EDC) has several scientific and methodological benefits. The availability of a large Type 1 population having 10 years of baseline periodontal and medical data is a valuable asset. This inter-institutional collaboration has demonstrated reliable examination methodologies as well as the ability to share data management and statistical resources. An integrated multidisciplinary effort provides significant data collection capabilities essential for understanding the complex multifactorial etiology of periodontal disease in Type 1 diabetes.